Lifting Device

ABSTRACT

The invention relates to a lifting device using fluid as a damping medium to form a driving force. It has an outer tube, an inner tube, a guiding assembly and a spring using fluid as a damping medium to achieve a lifting effect, one end of the inner tube being inserted in the outer tube from one end of the outer tube and being fixedly connected with the guiding assembly, a portion of the guiding assembly being in contact with the inner wall surface of the outer tube to implement rolling friction or sliding friction, one end of the spring being positioned in the outer tube, the other end of the spring penetrating through the inner tube and being connected with the inner tube

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to Chinese Patent Application No.201721919596.0, with a filing date of Dec. 29, 2017. The content of theaforementioned application, including any intervening amendmentsthereto, is incorporated herein by reference.

TECHNICAL FIELD

The invention relates to a lifting device using fluid as a dampingmedium to form a driving force.

BACKGROUND ART

A table which serves as an article for daily life is common in life,work and school learning. Along with improvement of living quality ofpeople, requirements for functions of the table are more and more, forexample, a requirement for the lifting function of the table is one ofthe requirements.

At present, lifting of most of tables is realized by gas springmechanisms mounted on table legs, for example, an invention patent withthe publication number being CN106308039A discloses a lifting device,and the lifting device comprises a spring which provides a holding forceafter lifting and uses fluid as a damping medium, a first sleeve and asecond sleeve; one end of the spring is positioned in the first sleeveand is fixedly connected with one end of the first sleeve; one end ofthe second sleeve is inserted in the first sleeve from the other end ofthe first sleeve, the other end of the spring penetrates through thesecond sleeve, the spring and the second sleeve are fixedly connected,and a guiding assembly used for the second sleeve to lift is arranged onthe first sleeve and/or the second sleeve; and the guiding assembly is arolling friction assembly or a sliding friction assembly.

In the above lifting device, although the rolling friction assembly hasa guiding effect on the second sleeve, the first sleeve is generallyfilled with lubricating oil to ensure the service life of the rollingfriction assembly, and by the lubricating effect of the lubricating oil,a friction force between the rolling friction assembly and the firstsleeve is reduced. However, for the lifting device, in a rising processof the second sleeve, the lubricating oil on the surface of the secondsleeve is exposed on the outside of the first sleeve along with risingof the second sleeve, the guiding assembly mounted at an end of thefirst sleeve is the rolling friction assembly or the sliding frictionassembly, and therefore, no components can stop exposure of thelubricating oil. After the second sleeve rises and is positioned, thelubricating oil on the surface of the second sleeve is exposed in air,in a using process of the lifting device, a user easily touches thelubricating oil, the lubricating oil which is exposed in the air iseasily oxidized and becomes dry due to loss of water under flowing ofthe air, and thus, the lubricating effect is lost.

SUMMARY OF THE INVENTION

The invention aims to provide a lifting device, and in the invention,lubricating oil which is attached to an inner tube can be scraped backinto an outer tube when the inner tube lifts.

The technical solution for solving the technical problem is as follows:

The lifting device comprises an outer tube, an inner tube, a guidingassembly and a spring using fluid as a damping medium to achieve alifting effect, one end of the inner tube is inserted in the outer tubefrom one end of the outer tube and is fixedly connected with the guidingassembly, a portion of the guiding assembly is in contact with the innerwall surface of the outer tube to implement rolling friction or slidingfriction, one end of the spring is positioned in the outer tube, theother end of the spring penetrates through the inner tube and isconnected with the inner tube, the end, which allows the inner tube tobe inserted, of the outer tube is connected with an oil scrapingmechanism, and the inner tube penetrates through the oil scrapingmechanism and is in clearance fit with the oil scraping mechanism.

Further, the guiding assembly comprises a chock plug with one endinserted in the inner tube, the chock plug comprises an inner sleeve, anouter assembling tube, a connecting block and rolling elements, one endof the connecting block is connected to the outer peripheral surface ofthe inner sleeve, the other end of the connecting block is connected tothe inner peripheral surface of the outer assembling tube, a groove isformed in the outer peripheral surface of the outer assembling tube,through holes are formed in the peripheral surface of the inner tube,one portion of each rolling element is positioned in the groove of theouter assembling tube, and the other portion of each rolling elementpenetrates through the corresponding through hole of the inner tube andthen is in contact with the inner surface of the outer tube.

Further, the oil scraping mechanism comprises a rubber ring.

Further, one end of the rubber ring is bent towards the inside of therubber ring to form a first bent portion, and the other end of therubber ring is bent towards the inside of the rubber ring to form asecond bent portion. Further, the oil scraping mechanism furthercomprises a connecting tube, one end of the connecting tube is fixedlyconnected with one end of the inner tube, and the other end of theconnecting tube is connected with the rubber ring.

Further, an annular groove is formed in the inner peripheral surface ofthe connecting tube, a first protrusion portion which extends in theradial direction of the rubber ring is arranged on the outer peripheralsurface of the rubber ring, and the first protrusion portion is embeddedin the annular groove.

Further, a second protrusion portion is also arranged on the outerperipheral surface of the rubber ring, and after the first protrusionportion is embedded in the annular groove, the first protrusion portionis abutted against the inner peripheral surface of the connecting tube.

After the lifting device of the present utility model is provided withthe oil scraping mechanism and the inner tube penetrates through the oilscraping mechanism and is in clearance fit with the oil scrapingmechanism, the oil scraping mechanism scraps most of the lubricating oilon the surface of the inner tube back into the outer tube when the innertube lifts, thus, the lubricating oil which is brought out to theoutside of the outer tube by the inner tube can be greatly reduced, andthe lubricating property of the lubricating oil can be maintained.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of an external structure of a lifting deviceof the present utility model;

FIG. 2 is a schematic sectional view of the lifting device of thepresent utility model;

FIG. 3 is schematic assembled view of a guiding assembly and an innertube in the present utility model;

FIG. 4 is a perspective schematic view of a rubber ring in the presentutility model;

FIG. 5 is a schematic sectional view of the rubber ring in the presentutility model;

FIG. 6 is a perspective schematic view of a connecting tube in thepresent utility model; and

FIG. 7 is a schematic sectional view of the connecting tube in thepresent utility model.

DETAILED DESCRIPTION OF THE UTILITY MODEL

As shown in FIG. 1 and FIG. 2, a lifting device of the present utilitymodel comprises an outer tube 1, an inner tube 2, a guiding assembly, anoil scraping mechanism and a spring 3 using fluid as a damping medium toachieve a lifting effect, and their structures and the relationshipbetween the structures will be described in detail:

As shown in FIG. 1 to FIG. 3, one end of the inner tube 2 is inserted inthe outer tube 1 from one end of the outer tube 1 and is fixedlyconnected with the guiding assembly, a portion of the guiding assemblyis in contact with the inner wall surface of the outer tube to implementrolling friction or sliding friction, the guiding assembly comprises achock plug with one end inserted in the inner tube, the chock plugcomprises an inner sleeve 4, an outer assembling tube 5, a connectingblock 6 and rolling elements 7, one end of the connecting block 6 isconnected to the outer peripheral surface of the inner sleeve 4, theother end of the connecting block 6 is connected to the inner peripheralsurface of the outer assembling tube 5, a groove is formed in the outerperipheral surface of the outer assembling tube 5, through holes areformed in the peripheral surface of the inner tube 2, one portion ofeach rolling element 7 is positioned in the groove of the outerassembling tube 5, the other portion of each rolling element 7penetrates through the corresponding through hole of the inner tube 2and then is in contact with the inner surface of the outer tube 1, andthus, each rolling element 7 is in contact with the inner wall surfaceof the outer tube 1 to implement rolling friction. The rolling elements7 can be spherical rolling elements or columnar rolling elements.

As shown in FIG. 1 and FIG. 2, the spring 3 is a gas spring, one end ofthe spring 3 is positioned in the outer tube 1, the other end of thespring 3 penetrates through the inner tube 2 and is connected with theinner tube 2, and thus, the inner tube 2 is driven to lift when thespring 3 lifts. The spring 3 penetrates through the inner sleeve 4 andthen penetrates through the inner tube 2, and the spring 3 and the innertube 2 can be directly connected (such as welding or threaded connectionor hinging), and can also be connected by an added connector (not shownin the figures).

As shown in FIG. 1 to FIG. 7, the end, which allows the inner tube 2 tobe inserted, of the outer tube 1 is connected with the oil scrapingmechanism, and the inner tube 2 penetrates through the oil scrapingmechanism and is in clearance fit with the oil scraping mechanism. Whenthe inner tube 2 lifts, most of lubricating oil attached to the surfaceof the inner tube 2 is scraped back into the outer tube by the oilscraping mechanism, thus, the lubricating oil which is brought out tothe outside of the outer tube 1 by the inner tube 2 can be greatlyreduced, and the lubricating property of the lubricating oil can bemaintained. Meanwhile, the oil scraping mechanism has a guiding effecton the inner tube 2, and because the two ends of the inner tube 2 areguided, the inner tube 2 can be more stable in a lifting process.

As shown in FIG. 1 to FIG. 7, the oil scraping mechanism comprises arubber ring 9, one end of the rubber ring 9 is bent towards the insideof the rubber ring 9 to form a first bent portion 9 a, the other end ofthe rubber ring 9 is bent towards the inside of the rubber ring 9 toform a second bent portion 9 b, by the first bent portion 9 a and thesecond bent portion 9 b, the lubricating oil attached to the surface ofthe inner tube 2 can be scraped back into the outer tube 1 regardless ofrising and falling of the inner tube 2, and therefore, the efficiency ofscraping the lubricating oil back into the outer tube is furtherimproved after the first bent portion 9 a and the second bent portion 9b are arranged.

As shown in FIG. 1 to FIG. 7, the oil scraping mechanism furthercomprises a connecting tube 10, one end of the connecting tube 10 isfixedly connected with one end of the inner tube 2, and the other end ofthe connecting tube is connected with the rubber ring 9. In one or moreembodiments, preferably, inner threads are arranged at the end, which isconnected with the inner tube 2, of the connecting tube 10, the innertube 2 is provided with outer threads, and therefore, the connectingtube 10 is in threaded connection with the inner tube 2. According to amode of connecting the connecting tube 10 with the rubber ring 9, anannular groove 10 a is formed in the inner peripheral surface of theconnecting tube 10, a first protrusion portion 9 c which extends in theradial direction of the rubber ring 9 is arranged on the outerperipheral surface of the rubber ring 9, the first protrusion portion 9c is embedded in the annular groove 10 a, and thus, the rubber ring 9and the connecting tube 10 are connected to form a whole body. Theconnecting mode is simple and reliable, and the first protrusion portion9 c can be rapidly embedded in the annular groove 10 a by the elasticeffect of the rubber ring favorably.

As shown in FIG. 1 to FIG. 7, a second protrusion portion 9 d is furtherarranged on the outer peripheral surface of the rubber ring 9, and afterthe first protrusion portion 9 c is embedded in the annular groove 10 a,the second protrusion portion 9 d is abutted against the innerperipheral surface of the connecting tube 10. After the rubber ring 9 isin clearance fit with the inner tube 2, the rubber ring 9 is extruded bythe inner tube 2 to move towards the inner wall of the connecting tube10, the second protrusion portion 9 d is abutted against the innerperipheral surface of the connecting tube 10, thus, the area of theportion, which is in contact with the connecting tube 10, of the rubberring 9 is increased, and the rubber ring 9 and the connecting tube arecombined more firmly.

We claims:
 1. A lifting device, comprising an outer tube, an inner tube,a guiding assembly and a spring using fluid as a damping medium toachieve a lifting effect, one end of the inner tube being inserted inthe outer tube from one end of the outer tube and being fixedlyconnected with the guiding assembly, a portion of the guiding assemblybeing in contact with the inner wall surface of the outer tube toimplement rolling friction or sliding friction, one end of the springbeing positioned in the outer tube, the other end of the springpenetrating through the inner tube and being connected with the innertube, characterized in that the end, which allows the inner tube to beinserted, of the outer tube is connected with an oil scraping mechanism,and the inner tube penetrates through the oil scraping mechanism and isin clearance fit with the oil scraping mechanism.
 2. The lifting deviceaccording to claim 1, characterized in that the guiding assemblycomprises a choke plug with one end inserted in the inner tube, thechoke plug comprises an inner sleeve, an outer assembling tube, aconnecting block and rolling elements, one end of the connecting blockis connected to the outer peripheral surface of the inner sleeve, theother end of the connecting block is connected with the inner peripheralsurface of the outer assembling tube, a groove is formed in the outerperipheral surface of the outer assembling tube, through holes areformed in the peripheral surface of the inner tube, one portion of eachrolling element is positioned in the groove of the outer assemblingtube, the other portion of each rolling element penetrates through thecorresponding through hole of the inner tube and then is in contact withthe inner surface of the outer tube.
 3. The lifting device according toclaim 1, characterized in that the oil scraping mechanism comprises arubber ring.
 4. The lifting device according to claim 3, characterizedin that one end of the rubber ring is bent towards the inside of therubber ring to form a first bent portion, and the other end of therubber ring is bent towards the inside of the rubber ring to form asecond bent portion.
 5. The lifting device according to claim 3,characterized in that the oil scraping mechanism further comprises aconnecting tube, one end of the connecting tube is fixedly connectedwith one end of the inner tube, and the other end of the connecting tubeis connected with the rubber ring.
 6. The lifting device according toclaim 5, characterized in that an annular groove is formed in the innerperipheral surface of the connecting tube, a first protrusion portionwhich extends in the radial direction of the rubber ring is arranged onthe outer peripheral surface of the rubber ring, and the firstprotrusion portion is embedded in the annular groove.
 7. The liftingdevice according to claim 6, characterized in that a second protrusionportion is further arranged on the outer peripheral surface of therubber ring, and after the first protrusion portion is embedded in theannular groove, the second protrusion portion is abutted against theinner peripheral surface of the connecting tube.